Air Safety Foundation says carbon monoxide accidents rare but deadly, offers safety advice
The AOPA Air Safety Foundation says accidents caused by carbon monoxide poisoning are extremely rare but recommends pilots install inexpensive CO detectors in their aircraft. ASF also suggests pilots and mechanics redouble efforts to recognize and prevent aircraft exhaust system leaks. “A search of the Air Safety Foundation accident database revealed only two accidents caused by carbon monoxide between 1985 and 1994,” said ASF Executive Director Bruce Landsberg. “But while accidents are rare, carbon monoxide can be insidious and deadly.”
A Piper Dakota crashed January 17 near Alton, New Hampshire, after the pilot and passenger became incapacitated. The state medical examiner said both had suffered from carbon monoxide poisoning. NTSB investigators found a small “corrosion-type” hole in the aircraft muffler.
The cabin heating system in the Dakota—like most single-engine aircraft—provides heat by passing ambient air from the engine compartment through a shroud surrounding the exhaust muffler enroute to cabin heat outlets. A leak in the exhaust system could allow carbon monoxide gas to enter the cabin. Carbon monoxide—an odorless, tasteless, colorless gas—causes hypoxia when inhaled, reducing the blood’s ability to carry oxygen. That can lead to headache, drowsiness, dizziness, or even loss of consciousness and death.
“If you smell exhaust fumes in the cabin, you should immediately shut off the heater and open fresh air vents, even the storm window,” said Landsberg. “If you ever get a headache or become sleepy, dizzy, or nauseous, suspect carbon monoxide and get fresh air immediately. Carbon monoxide can enter the cockpit without a detectable exhaust smell.”
Landsberg noted there are several different styles of carbon monoxide detectors available for aircraft use. The Air Safety Foundation recommends installing a CO detector and including it in the pilot’s instrument scan anytime cabin heat is in use. The safety foundation noted that the inexpensive cardboard “dot” detectors that change color when exposed to CO gas must be replaced every 30 days. New technology detectors with a longer useful life are now coming on the market.
“Most importantly, pilots should be sure their mechanics carefully check the entire exhaust system at each annual inspection,” said Landsberg. “As aircraft age, regular inspection and maintenance become increasingly important.”
The AOPA Air Safety Foundation is general aviation’s independent, nonprofit organization chartered in 1950 to improve general aviation safety. ASF produces videotapes, pamphlets, newsletters, and other materials for continuing pilot education. It conducts more than 300 safety seminars and Flight Instructor Refresher Clinics throughout the United States annually.
January 23, 1997